2003 2.3 has no ground at starter relay dark blue/ orange wire . If jumped to ground will crank but no start ? Thanks for any advise .

 

Welcome to the forum

Your PATS(passive anti-theft system) has been activated, it disables starter relay(no ground) but also disable fuel pump, and the big one, no fuel injectors, so no "work around" for this

There is a THEFT light on the dash, it will start to flash rapidly if PATS was triggered with Key On, let it flash and wait 45-60 seconds, it will start to flash a 2 digit code, one flash, followed by 1 to 6 flashes, then it will repeat code a few times


PATS uses a transponder key, there is an RFID Tag in the key's handle
With key on, PATS reads the tag number and compares that to the 3 or 4 key numbers it was programmed with at the factory, if no number or no match then no crank and no start, also THEFT light will start to flash
These are the codes
11 Transceiver [transponder coil] not connected, or there is no power to it.
12 Transceiver internal fault.
13 No Key/no PATS key has been used to turn the ignition switch.
14 Incomplete key code received.
15 Invalid key code received.
16 CAN communications error.

As said there is no temporary or work around when this happens, vehicle is suck where it sits, can be towed or you can get a mobile locksmith to come out and make a new PATS key and then use his laptop with Ford software to add that new key to the vehicles Memory, usually best to get TWO PATS keys, so you always have a spare

You can test battery voltage
Needs to be 12.3v to 12.8volts
12.2v or lower can cause PATS to trigger on startup
I mention this because a 2003 vehicle is 18 years old, battery's last 6 years, so you should be at "end of life" on the 3rd battery

 

Theft light not flashing when key is turned.theft light slowing blinks with key off

 

Then its an odd occurrence

PATS is IN the computer(PCM) in a 2003 Ranger
It grounds the starter relay if key in ignition passes the PATS test

Does the CEL(check engine light) come on with key on, this means PCM has booted up
No CEL means no PCM so no start, there is a PCM fuse and PCM relay in the engine fuse box

If CEL comes on then try to start engine, CEL should go OFF when engine is turning, that means PCM is getting a timing signal from crank sensor
No timing signal means no spark and no fuel injectors

If CEL goes OFF when cranking then try 50/50 test
Spray fuel into the engine
Try to start
If it starts and dies then spark is working but not fuel injectors......or fuel pump
If it doesn't start then no spark
50/50 instant results

 

No check engine light on when key is turned ?

 

Checked PCM relay and 30 amp fuse both seem to be good

 

Bummer

It could just be the PCM relay is not activating with key on, if possible put your finger on it and have someone turn on the key, you should feel it click closed
If you don't have a helper, disconnect negative battery cable, turn key to ON, then have finger on relay and hook negative cable back up, should feel it click
If not then that's the problem, swap it with another relay in the box, like wiper relay and see if that works

If relay is not closing then problem is ignition switch, under the steering column in the cab, or wire from that switch to PCM relay
Check fuse 19 in the cab fuse box, 25amp, that powers several Key ON systems, including 12v that closes PCM relay


If relay IS clicking closed then........................
You will need to remove the 104-wire connector from the computer
Should look like this: https://www.ford-trucks.com/forums/a...1&d=1052748771
Upper center of firewall

Pull out the bolt and wiggle connector until it comes out, you may need to cut wire ties or unbolt cable straps
Inspect connector for damage or corrosion

Then undo the bolts holding computer in firewall and pull it out, open up computer and inspect its circuit boards

The PCM has 3 12volt power wires
Pin 55 yellow wire is from fuse 21 in engine fuse box, has full time 12volts for memory backup
Pins 71 and 97, red wires, have key on 12volts, this powers up the PCM, from PCM fuse and PCM relay

Pin numbers seen here: https://www.explorerforum.com/forums...cm1-jpg.34210/
Engine size doesn't matter for this, all use the same 12v

 

No clicking on relay with key on. Already changed ignition under column with new one , fuse #19 good (ohams test) but no power checking with meter with key on . Did swap relays also no clicking closed with existing or new relay. Driving me nuts . Thks for all the help.

 

OK, there a long shot which is the PCM Diode, same size as a fuse and its next to the PCM relay has mark like this -->|--

Slot 53 if they are labelled, PCM relay is in 54

Pull it out and have a look, it has a DIRECTION so remember which way its facing, if it is in backwards PCM relay won't work
Replace it with a jumper wire, or a fuse that fits, to test if this is the problem
See if CEL comes on
If not then replace the diode, its not the problem

You can jump the PCM relay to see if this is the only problem
Pull out the PCM relay and look at the slots in fuse box base, should look like this: http://www.gtsparkplugs.com/images/m...iring-840x.jpg

Put a jumper wire between 30 and 87, these slots would be connected if relay closed

Ford also used Micro relays, their slots look like this: http://www.gtsparkplugs.com/images/m...lay-wiring.jpg
Same slots to jump, 30 to 87 just different lay out

Turn on key and CEL should be on, PCM powered up
Start engine

Test if fuse 19 in the cab has 12volts with key on
If not then light green/purple wire from ignition switch to fuse 19 is bad, it also powers fuse 11 in cab

If fuse 19 has power then the Red/light green wire from fuse 19 to the PCM diode is bad

 

One side of diode is totally rusted , placed jumper wire , engine light did come on but no start . Guessing a should change diode before moving on ?

 

Good work

You can leave the jumper in place for now and keep testing
The PCM diode is there as a surge suppressor, and should be cleaned up or replaced, it is OK to run the jumper for now

So does it now crank without grounding starter relay?
It should if PCM is now ON and grounding that relay

You could do the 50/50 test to see if its a spark or fuel issue no start

 

With jumper in diode and I replaced PCM relay with new one it did start ‼️‼️‼️ but not with key/ignition. I had to take ignition switch down from column and push manually.First time it started in months .

 

Good stuff

While ignition switch is out turn the key and check that the Actuator Rod is moving

Basic diagram of how steering column key mechanism works: https://www.2carpros.com/images/ques...1/original.gif

On the back of the key cylinder is a GEAR
When you turn the key the gear turns and UnLocks steering wheel and also pulls the Actuator rod up towards steering wheel
Actuator rod then pulls the ignition switch into its 4 positions, ACC, OFF, RUN, START

So hold the rod for the ignition switch and turn the key to make sure there is no looseness, rod should move as you turn the key

Parts inside steering column can break, and its a PAIN to fix and replace them, just a heads up



The Diode Ford uses can be found at most auto parts stores, they are not "Ranger" parts, you will find same Diode in any Ford car or truck, after 1995 or so